Scientific Origin Stories III::

Migrations and Diversifications

The conventional story continues: After the successive waves of cross-continental migrations, the heterogeneous northeastern Asian bands and their descendants continued hunting big game and gathering wild foods. Some, such as the descendants of the Inuit-Aleuts remained north. Others pressed southwards along the Rocky Mountains and migration pushed different bands across the continent to the Atlantic coast and down into Central and South America.

Over time, more cultural and genetic differentiation occurred as bands merged and split and new bands appeared. The Inuit split off from the Aleuts, for example, and some groups split off from the Athapaskan and moved south to become descendants of today's Navajo or Dine and Apache.

As the Ice Age drew to a close, some 10,000 to 7000 years ago, geographical changes caused more cultural adaptations and diversifications: the great mammoths; giant bison, bears and sloth; prehistoric horses and other animals became extinct as the great glaciers receded, and vast swathes of grassland prairies, hardwood forests, arid Plains, plateaux and jungles appeared over the Americas.

For the most part, prehistoric American hunting methods adapted to the relatively smaller animals such as deer and antelope. As the land changed, coastal peoples concentrated their efforts on fish harvesting and shellfish collecting; woodland peoples used fire to clear the land and encourage the deer and other animals; in the Canadian north, bands hunted wearing snow-shoes and herded the caribou into corrals; and in Mexico, people began to farm, growing corn, beans and squash.